diff --git a/man3/getumask.3 b/man3/getumask.3
index 4e6b092a7..9c61d3ceb 100644
--- a/man3/getumask.3
+++ b/man3/getumask.3
@@ -60,5 +60,8 @@ This is a vaporware GNU extension.
 .SH NOTES
 This function is documented in the glibc manual, but,
 as at glibc version 2.24, it is not implemented on Linux.
+(See
+.BR umask (2)
+for a thread-safe method of discovering a process's umask.)
 .SH SEE ALSO
 .BR umask (2)